The new OPL4D from Yamaha Co’s Systems Technology Division is a lower cost version of the OPL4 which was announced in 1993. The substitution of dynamic for static RAM has helped reduce the cost. Both chips provide FM-enhanced wave table for use in computers. The new OPL4D enables easy uploading of special sounds. It has power-down mode, needs fewer supporting components and is pin-compatible with the OPL4. The new OPL4D incorporates the necessary ROM and RAM to provide the full range of wave table sound. It is backwards-compatible with the OPL4. The OPL4D is available in the standard 80-pin plastic quad flat pack which is backward compatible with the OPL4, and a new slim 100-pin SQFP version, called the OPL4S, especially suitable for PCMCIA applications. The OPL4D chip set is $28 in 10,000-up quantities. The OPL4S chip set is $29 in 10,000-up quantities, and both include the Digital to Analogue Converter and ROM.
